scholarly journals Ways to determine reliability in the operation of ship parts made by banding method

2021 ◽  
pp. 37-43
Author(s):  
Ivan Kovalenko
Keyword(s):  
Welded Joints ◽  
Operating Conditions ◽  
Special Role ◽  
Structural Class ◽  
Fine Grained ◽  
Special Factor ◽  
Structural Lattice ◽  
Fine Grained Structure ◽  
Materials Used ◽  
Selection Of

In the development of modern shipbuilding conditions and the repair of ship units, a special role is given to the use of basic structural elements consisting of technological parts. When performing these steps, it is important to analyze the properties of the materials from which the technological components of ship equipment are made. Testing should be close to the operating conditions of ship axles and shafts, namely cyclic loading, aggressive and adhesive environment. Therefore, a special factor is the technological control over the sequence of manufacture, selection of materials, surfacing technology. All these requirements can be analyzed and predicted using computer modulation. Investigations of the properties of the transition layers of the weld and the base metal and their effect on the number of load cycles in the tests are also key. All conditions will be met with the optimal selection of the chemical component Ni - Cr, which provide the required level of doping. The hardness of the materials is ensured by the presence of Mg in the metal. Also important are the heat treatment modes that provide the desired final structure of the material for machining and surfacing. For this part and its elements, the best properties in terms of operation in fine austenitic and pearlitic structures. During the operation of ship shafts and axles, the propagation of puncture loads is performed due to the occurrence of final stresses at low-cycle and multi-cycle loads and subsequent fatigue of the structural lattice. When considering the range of materials used in combined structures is very large and includes most welded steels. According to the combination of materials in one unit, it is advisable to distinguish two main groups of structures: with welded joints of steels of the same structural class, but different alloying, and with welded joints of steels of different structural classes. In this regard, the decision to obtain a balanced bandage connection lies in obtaining a fine-grained structure of the weld metal and the seam area.

scholarly journals Material Origins of the Accelerated Operational Wear of RD-33 Engine Blades

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 336
Author(s):  
Adam Kozakiewicz ◽  
Stanisław Jóźwiak ◽  
Przemysław Jóźwiak ◽  
Stanisław Kachel
Keyword(s):  
Chemical Composition ◽  
Construction Material ◽  
Operating Conditions ◽  
Design Stage ◽  
Strength Analysis ◽  
Jet Engine ◽  
Emergency Situations ◽  
Materials Used ◽  
Propulsion Unit ◽  
Selection Of

The structural and strength analysis of the materials used to construct an important engine element such as the turbine is of great significance, at both the design stage and during tests and training relating to emergency situations. This paper presents the results of a study on the chemical composition, morphology, and phased structure of the metallic construction material used to produce the blades of the high- and low-pressure turbines of the RD-33 jet engine, which is the propulsion unit of the MiG-29 aircraft. On the basis of an analysis of the chemical composition and phased structure, the data obtained from tests of the blade material allowed the grade of the alloy used to construct the tested elements of the jet engine turbine to be determined. The structural stability of the material was found to be lower in comparison with the engine operating conditions, which was shown by a clear decrease in the resistance properties of the blade material. The results obtained may be used as a basis for analyzing the life span of an object or a selection of material replacements, which may enable the production of the analyzed engine element.

Selection of Rational Deformation Pressing Modes in a Special Device

2021 ◽  
Vol 316 ◽  
pp. 319-323
Author(s):  
Assemgul Uderbayeva ◽  
Ayaulym Rakhmatulina ◽  
Gulzira Nurakhmetova
Keyword(s):  
Aluminum Alloy ◽  
Aluminum Alloys ◽  
Continuous Casting ◽  
Strength Properties ◽  
Special Device ◽  
Fine Grained ◽  
Fine Grained Structure ◽  
Selection Of

Various types of deformed semi-finished products are prepared from aluminum alloys, such as plates, sheets, tapes, foil, panels, profiles, pipes, rods, forged pieces, wires. These semi-finished products are obtained by processing ingots of continuous casting by pressure - rolling, rolling-off, pressing, forging, stamping or drawing. Pressed semi-finished products are made of aluminum alloys in the majority of cases. The work examines the study of the evolution of the half-finished products microstructure at different stages of their manufacturing in several passes and shows the possibility of obtaining strips of fine-grained structure using pressing in a special device. Also, the research established that, in the material of half-finished product from the AD31 aluminum alloy the smooth fine-grained structure is formed with grains of 6 - 17 μm, which leads to an increase in the strength properties of the alloy and to a preservation of good plasticity.

scholarly journals Studies on the influence of Alti5b1 modifier on the structure and properties of alcumg ALLOYS

2021 ◽  
pp. 37-48
Author(s):  
Wojciech Ściężor ◽  
Radosław Kowal ◽  
Krystian Franczak ◽  
Justyna Grzebinoga ◽  
Paweł Kwaśniewski ◽  
...  
Keyword(s):  
Microstructural Analysis ◽  
Production Costs ◽  
Fine Grained ◽  
Mechanical And Electrical Properties ◽  
Alloying Additives ◽  
Fine Grained Structure ◽  
Cast Alloys ◽  
Materials Used ◽  
Alloy Properties ◽  
Different Content

New materials used in various industries require sufficiently high mechanical properties, fine-grained structure and ease of metal forming while minimizing production costs. For this reason, work is being carried out to develop new groups of alloys that make it possible to increase the strength of the obtained components while reducing their weight, and thus reducing production costs. This article focuses on two aluminium-based alloys with different content of alloying additives: copper and magnesium i.e., AlCu3Mg3 and AlCu4.5Mg6, which were produced by metallurgical synthesis. The as-cast alloys were characterized for their basic physical, mechanical and electrical properties and were subjected to structural analysis. In the next stage, the alloys were modified with 100, 500, 1000 and 2000 ppm of titanium and then their hardness, electrical conductivity and density were tested. Samples were also subjected to microstructural analysis. The obtained results allowed to examine the evolution of the AlCuMg alloy properties depending on the content of alloy additives and the amount of used modifier.

MODERN EQUIPMENT FOR DETERMINING TRACTOR-SPEED PROPERTIES OF THE VEHICLE: CHARACTERISTICS’ ANALYSIS IN LABORATORY CONDITIONS

2019 ◽  
Vol 16 (3) ◽  
pp. 276-289
Author(s):  
N. V. Savenkov ◽  
V. V. Ponyakin ◽  
S. A. Chekulaev ◽  
V. V. Butenko
Keyword(s):  
Environmental Performance ◽  
Operating Conditions ◽  
Special Role ◽  
Development Stages ◽  
Advantages And Disadvantages ◽  
Force Transfer ◽  
Characteristics Analysis ◽  
And Performance ◽  
Loading Devices ◽  
Structural Solutions

Introduction. At present, stands with running drums are widely used for various types of tests. Power stands play a special role. Such stands take the mechanical power from the driving wheels of the car. This simulates the process of movement of the vehicle under operating conditions. Such equipment has various designs, principles of operation and performance. It is also used in tests that are different by purpose, development stages and types: research, control, certification, etc. Therefore, it is necessary in order to determine the traction-speed, fuel-efficient and environmental performance characteristics.Materials and methods. The paper provides the overview of the power stands with running drums, which are widespread on the domestic market. The authors carried out the analysis of the main structural solutions: schemes of force transfer between the wheel and the drum; types of loading devices; transmission layout schemes and features of the control and measuring complex. The authors also considered corresponding advantages and disadvantages, recommended spheres of application, demonstrated parameters and characteristics of the units’ workflow, presented components and equipment.Discussion and conclusions. The authors critically evaluate existing models of stands with running drums. Such information is useful for choosing serial models of stands and for developing technical tasks for designing or upgrading the equipment.

scholarly journals Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff
Keyword(s):  
Large Scale ◽  
Measurement Data ◽  
Fine Grained ◽  
Dredged Materials ◽  
Measurement Results ◽  
Large Scale Field ◽  
Eigenvalue Ratio ◽  
Ill Posed ◽  
Materials Used ◽  
Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

scholarly journals Analysis and Comparative Assessment of Basic Tribological Properties of Selected Polymer Composites

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 75 ◽  
Author(s):  
Jerzy Jozwik ◽  
Krzysztof Dziedzic ◽  
Marcin Barszcz ◽  
Mykhaylo Pashechko
Keyword(s):  
Polymer Composites ◽  
Friction Force ◽  
Tribological Properties ◽  
Friction Pair ◽  
Computer Software ◽  
Operating Conditions ◽  
The Coefficient Of Friction ◽  
Cast Polyamide ◽  
Friction Path ◽  
Materials Used

Phenomena occurring in the contact area between two mating bodies are characterised by high complexity and variability. Comparisons are usually made between parameters such as the coefficient of friction, friction force, wear and temperature in relation to time and friction path. Their correct measurement enables the proper evaluation of tribological properties of materials used in the friction pair. This paper concerns the measurements of basic tribological parameters in the friction of selected polymer composites. Knowing the tribological properties of these composite materials, it will be possible to create proper operating conditions for kinematic friction pairs. This study investigated the coefficients of friction, friction force and temperatures of six polymer composites: cast polyamide PA6 G with oil, PA6 G with MoS2, polyoxymethylene POM with aluminium, polyethylene terephthalate PET with polytetrafluoroethylene PTFE, PTFE with bronze, and PTFE with graphite. The friction surface was also examined using an optical system and computer software for 3D measurements. As a result, PA6-G with oil was found to be the best choice as a composite material for thin sliding coatings.

Quality Assessment of Weldable Steel Mark P355NH from Decompression Chamber Construction for Diving

2012 ◽  
Vol 217-219 ◽  
pp. 2381-2387
Author(s):  
Doru Romulus Pascu ◽  
Radu Alexandru Roşu ◽  
Iuliana Duma ◽  
Horia Daşcău
Keyword(s):  
Test Temperature ◽  
Transverse Direction ◽  
Mechanical Characteristics ◽  
Longitudinal Direction ◽  
Pressure Vessels ◽  
Fine Grained ◽  
Weldable Steel ◽  
Breaking Energy ◽  
Fine Grained Steels ◽  
Selection Of

Non-alloyed P355NH steel according to EN 10028-3:2003 belongs to a group of fine-grained steels for pressure vessels being used in welded construction at decompression chamber for divers. Values of the chemical, structural and mechanical characteristics and steel toughness experimentally determined fit the analyzed steel in P355NH steel group according to EN 10028-3:2003. The toughness of the analyzed steel at the test temperature of -30°C is characterized by high values of fracture energy KV in longitudinal direction between 48 and 86 J and on transverse direction between 17 and 34J. Steel toughness at the test temperature of -30°C required by ABS standard (in Section 4/5.3 and Table 1) provides for breaking energy KV of min. 35J, with ductile fracture surfaces, value that is not respected at some lots of the three batches (A, B, C) of steel. Finally, based on the direct correlation established between HV10 hardness of the fine structure and the toughness it was made a selection of the lots of non-alloy steel P355NH which correspond to ABS norm for welded construction of the decompression chamber for divers

Adaptation Application to Engine Modelling

2007 ◽  
Author(s):  
Jude Iyinbor
Keyword(s):  
Measurement Data ◽  
Engine Performance ◽  
Performance Model ◽  
Operating Conditions ◽  
Adaptation Process ◽  
Design Point ◽  
Component Map ◽  
Important Measurement ◽  
Unknown Component ◽  
Selection Of

The optimisation of engine performance by predictive means can help save cost and reduce environmental pollution. This can be achieved by developing a performance model which depicts the operating conditions of a given engine. Such models can also be used for diagnostic and prognostic purposes. Creating such models requires a method that can cope with the lack of component parameters and some important measurement data. This kind of method is said to be adaptive since it predicts unknown component parameters that match available target measurement data. In this paper an industrial aeroderivative gas turbine has been modelled at design and off-design points using an adaptation approach. At design point, a sensitivity analysis has been used to evaluate the relationships between the available target performance parameters and the unknown component parameters. This ensured the proper selection of parameters for the adaptation process which led to a minimisation of the adaptation error and a comprehensive prediction of the unknown component and available target parameters. At off-design point, the adaptation process predicted component map scaling factors necessary to match available off-design point performance data.

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